Consider the following glossary Sx x x is scary Fx x x is a
Consider the following glossary:
Sx: {x: x is scary}
Fx: {x: x is a film}
Rx: {x: x is romantic}
Ax: {x: x is afraid}
a = Alex
b = Alyssa
Using this glossary, select the best translation of the following english sentences into MPL:
1.1. Every scary film is not romantic.
[1] ¬x((Sx F x) ¬Rx)
[2] x((Sx F x) ¬Rx)
[3] x((Rx F x) Sx)
[4] ¬x((¬Sx F x) Rx)
1.2. Every romantic film is scary.
[1] ¬x((Sx F x) Rx)
[2] x((Sx F x) Rx)
[3] ¬x((Sx ¬F x) Rx)
[4] x((Rx F x) Sx)
1.3. Either Alex is scary, or he is romantic and he is unafraid.
[1] (Sa (Ra ¬Aa))
[2] (Sa (Rb Aa))
[3] (¬Sa (Ra Aa))
[4] (Sb (Ra Aa))
1.4. Not every unromantic film is scary.
[1] ¬x((Rx ¬Sx) F x)
[2] x(Rx (Sx F x))
[3] ¬x((F x ¬Rx) Sx)
[4] ¬x((F x Rx) ¬Sx)
1.5. If Alex is afraid if and only if Alyssa is scary, then Alex is unafraid.
[1] (Aa (Sb Aa))
[2] ((Aa Sb) ¬Aa)
[3] ((Aa Sb) Aa)
[4] ((Aa Sb) Aa)
1.6. If Alex is romantic just in case some film is scary, then Alex is not romantic.
[1] ((Ra x(F x Sx)) ¬Ra)
[2] (Ra x((F x Sx) Rx))
[3] (Ra x((F x Sx) ¬Rx))
[4] ((Ra x((F x Sx)) ¬Rx))
1.7. Alex is not romantic and Alyssa is scary, only if Alyssa being scary is sufficient for Alex to not be romantic.
[1] ((¬Ra (Sb ¬Ra)) Sb)
[2] ((¬Ra Sb) (Sb ¬Ra))
[3] ((¬Ra (Ra ¬Sb)) Sb)
[4] ((¬Ra Ra) ¬Sb) Sb)
1.8. If every film is not scary, then Alex is afraid only if Alyssa is unafraid.
[1] (x(F x ¬Sx) (Aa ¬Ab))
[2] x(F x (¬Sx (Aa Ab)))
[3] ((Aa Ab) x(F x ¬Sx))
[4] x(F x (¬Sx (Aa Ab)))
1.9. If every scary film is romantic unless it isn’t, then no scary film is romantic.
[1] (x((Sx F x) (¬Rx Rx)) ¬x(Sx (Rx F x)))
[2] (x((Sx F x) (Rx Rx)) ¬x(Sx (Rx F x)))
[3] (x((Sx F x) (Rx Rx)) ¬x(Sx (Rx F x)))
[4] (x((Sx F x) (¬Rx ¬Rx)) ¬x(Sx (Rx F x))))
1.10. Alex is not romantic but Alyssa is unless Alex is scary.
[1] (¬Ra (Sa Rb))
[2] (¬Ra (¬Rb ¬Sa))
[3] (¬Ra (Rb Sa))
[4] (¬Ra (¬Rb Sa))
Solution
1.1. Every scary film is not romantic.
Ans : [2] x((Sx F x) ¬Rx)
1.2. Every romantic film is scary.
Ans: [4] x((Rx F x) Sx)
1.3. Either Alex is scary, or he is romantic and he is unafraid.
Ans: [1] (Sa (Ra ¬Aa))
1.4. Not every unromantic film is scary.
Ans: [3] ¬x((F x ¬Rx) Sx)


